Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico
In marine basins, gas hydrate systems are usually identified by a bottom simulating reflection (BSR) that parallels the seafloor and coincides with the base of the gas hydrate stability zone (GHSZ). We present a newly discovered gas hydrate system, Moby-Dick, located in the Ship Basin in the norther...
Published in: | Geology |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Geological Society of America
2021
|
Subjects: | |
Online Access: | https://hdl.handle.net/10037/22219 https://doi.org/10.1130/G49310.1 |
id |
ftunivtroemsoe:oai:munin.uit.no:10037/22219 |
---|---|
record_format |
openpolar |
spelling |
ftunivtroemsoe:oai:munin.uit.no:10037/22219 2023-05-15T14:26:06+02:00 Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico Portnov, Alexey Cook, A.E. Vadakkepuliyambatta, Sunil 2021-08-12 https://hdl.handle.net/10037/22219 https://doi.org/10.1130/G49310.1 eng eng Geological Society of America Geology Norges forskningsråd: 223259 info:eu-repo/grantAgreement/RCN/SFF/223259/Norway/Centre for Arctic Gas Hydrate, Environment and Climate/CAGE/ Portnov AD, Cook, Vadakkepuliyambatta S. Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico. Geology. 2021;49 FRIDAID 1927030 doi:10.1130/G49310.1 0091-7613 1943-2682 https://hdl.handle.net/10037/22219 openAccess Copyright © 2021 Geological Society of America VDP::Mathematics and natural science: 400::Geosciences: 450 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450 Journal article Tidsskriftartikkel Peer reviewed acceptedVersion 2021 ftunivtroemsoe https://doi.org/10.1130/G49310.1 2021-08-25T22:53:43Z In marine basins, gas hydrate systems are usually identified by a bottom simulating reflection (BSR) that parallels the seafloor and coincides with the base of the gas hydrate stability zone (GHSZ). We present a newly discovered gas hydrate system, Moby-Dick, located in the Ship Basin in the northern Gulf of Mexico. In the seismic data, we observe a channel-levee complex with a consistent phase reversal and a BSR extending over an area of ∼14.2 km2 , strongly suggesting the presence of gas hydrate. In contrast to classical observations, the Moby-Dick BSR abnormally shoals 150 m toward the seafloor from west to east, which contradicts the northward-shallowing seafloor. We argue that the likely cause of the shoaling BSR is a gradually changing gas mix across the basin, with gas containing heavier hydrocarbons in the west transitioning to methane gas in the east. Our study indicates that such abnormal BSRs can be controlled by gradual changes in the gas mix influencing the shape of the GHSZ over kilometers on a basin scale. Article in Journal/Newspaper Arctic University of Tromsø: Munin Open Research Archive Geology |
institution |
Open Polar |
collection |
University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
topic |
VDP::Mathematics and natural science: 400::Geosciences: 450 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450 |
spellingShingle |
VDP::Mathematics and natural science: 400::Geosciences: 450 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450 Portnov, Alexey Cook, A.E. Vadakkepuliyambatta, Sunil Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico |
topic_facet |
VDP::Mathematics and natural science: 400::Geosciences: 450 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450 |
description |
In marine basins, gas hydrate systems are usually identified by a bottom simulating reflection (BSR) that parallels the seafloor and coincides with the base of the gas hydrate stability zone (GHSZ). We present a newly discovered gas hydrate system, Moby-Dick, located in the Ship Basin in the northern Gulf of Mexico. In the seismic data, we observe a channel-levee complex with a consistent phase reversal and a BSR extending over an area of ∼14.2 km2 , strongly suggesting the presence of gas hydrate. In contrast to classical observations, the Moby-Dick BSR abnormally shoals 150 m toward the seafloor from west to east, which contradicts the northward-shallowing seafloor. We argue that the likely cause of the shoaling BSR is a gradually changing gas mix across the basin, with gas containing heavier hydrocarbons in the west transitioning to methane gas in the east. Our study indicates that such abnormal BSRs can be controlled by gradual changes in the gas mix influencing the shape of the GHSZ over kilometers on a basin scale. |
format |
Article in Journal/Newspaper |
author |
Portnov, Alexey Cook, A.E. Vadakkepuliyambatta, Sunil |
author_facet |
Portnov, Alexey Cook, A.E. Vadakkepuliyambatta, Sunil |
author_sort |
Portnov, Alexey |
title |
Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico |
title_short |
Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico |
title_full |
Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico |
title_fullStr |
Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico |
title_full_unstemmed |
Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico |
title_sort |
diverse gas composition controls the moby-dick gas hydrate system in the gulf of mexico |
publisher |
Geological Society of America |
publishDate |
2021 |
url |
https://hdl.handle.net/10037/22219 https://doi.org/10.1130/G49310.1 |
genre |
Arctic |
genre_facet |
Arctic |
op_relation |
Geology Norges forskningsråd: 223259 info:eu-repo/grantAgreement/RCN/SFF/223259/Norway/Centre for Arctic Gas Hydrate, Environment and Climate/CAGE/ Portnov AD, Cook, Vadakkepuliyambatta S. Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico. Geology. 2021;49 FRIDAID 1927030 doi:10.1130/G49310.1 0091-7613 1943-2682 https://hdl.handle.net/10037/22219 |
op_rights |
openAccess Copyright © 2021 Geological Society of America |
op_doi |
https://doi.org/10.1130/G49310.1 |
container_title |
Geology |
_version_ |
1766298581219672064 |